The usefulness of CA19-9 for early diagnosis of pancreatic cancer during the follow-up of benign pancreatic diseases

Aims: The usefulness of CA19-9 in high-risk individuals for PC remains unclear. This study aimed to clarify the clinical utility of CA19-9 during follow-up of benign pancreatic diseases.
Methods: We retrospectively reviewed patients diagnosed with PC during follow-up of benign pancreatic diseases at our hospital between January 2013 and March 2020. Among them, 30 patients undergoing regular blood test for three years prior to diagnosis of PC were enrolled (PC group). Eighty-three benign pancreatic disease patients, who had been followed up for at least one year and ruled out PC, were assigned to control group. CA19-9 levels at 0-3, 3-6, 6-12, 12-24, and 24-36 months before diagnosis of PC were compared. Indicative values were calculated by use of receiver operating characteristic curves.
Results: CA19-9 levels were higher in the PC group than the control group at 0-3 months (49.9 vs. 8.6 U/mL, P<0.001), 3-6 months (28.4 vs. 8.3 U/mL, P=0.001) and 6-12 months (14.2 vs. 9.2 U/mL, P=0.011). Twenty-seven patients in the PC group underwent imaging examinations (3 US, 12 CT, 12 MRI) at 6-12 months, but tumor could not be detected. The cutoff values of CA19-9 (Youden's index/specificity 80%/specificity 95%) were 19.1/36.7 at 6-12 months.
Conclusions: CA19-9 may be useful for early diagnosis of PC in high-risk individuals.